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As you may have gathered from the unboxing video, the VanMoof Electrified S is not my bike. But after a week of breaking it in I was able to borrow it for a short test ride. That's 45 minutes from Darmstadt towards Traisa, onwards to Eberstadt and back. This track has everything, from paved roads and bike paths to gravel. Enough to get a good understanding of the bike.

Not surprisingly it takes balls of steel to ride this bike. There is no suspension and the frame is as rigid as it gets. Certainly feels way better on blacktop than on bumpy paths. The ride is very solid and quiet. No rattling, no squeaking, the bike feels like a tank. Surprise: even on full power you never feel like the motor is running you. It's just a gentle push that won't end. Technically it will, but the bike has never been recharged since its first charge last week. And there is still juice in the battery.

The average speed would have been higher if I did not include so many gravel roads, but it was also not a leisure ride. I looked at my Apple Watch and my heart rate was at 150 uphill. I would have been able to go that same path on my normal bike, only slower.

That's what the VanMoof Electrified S does: you still get your exercise on the bike, you just arrive earlier.

Comments

I wonder what amount of calories the watch would count when the same person (weight etc.) would ride the same distance in the same time without support. Obviously heart rate would be higher, so count would be higher.

Now same experiment but different variable changed: same time, same intensity, still without e-support. This would obviously result in a shorter distance. Would it count less because of the shorter distance or same because of equal time+intensity?

Kai, you can set the max speed to either 25 km/h or 20 mph via the app. So it is up to stay within the limits set by law. Assuming a rider of 72 kg and a bike weight 18 kg we get to about 90 kg of mass. A third of that would be 30 kg? What is that? A small child on a tricycle?

How about a bit of basic engineering?

Kinetic energy equals mass divided by two and multiplied by velocity squared. At 90 kg mass and 25 km/h you get 2700 Joule. If you talk about a peloton going at 50 km/h and you solve for mass you get 28 kg at 2700 Joule. That's your max weight for rider plus bike on the same brake. How do you make a 22 kg rider on 6 kg bike that is capable of going 50 km/h? And if you go downhill at 80 km/h your max weight is 11 kg. That's a 5 kg rider.

I am pretty sure that the engineer who was specifying the brake was thinking 120 kg with 20 mph. That's 4800 Joule. If I take that kinetic energy and assume a really light rider/bike at 70 kg mass, you could only go 42 km/h. That's not enough for a peloton on flat terrain. Hence the bigger brakes.

Some riders keep telling you, they descended the alps with 140mm at 90kgs without any fading. However, cooling capacity increases with r-squared.
At least for spare parts, both rotors are at the same price point. So it comes down to aesthetics vs. safety and I even prefer the other look.

Speaking of an utility bike, you can easily ignore the riders with sports background. We are willing to spend bucks on lightweight tech we'll never need but forget to include the rider in our calculations :)
(hint: cutting weight is always cheaper as a new wheel-set)

But as the higher quality group sets are +160 and hydraulic only, it's easy to slag on choices outside that box.

The VanMoof is a beauty for urban cycling, won't question that. It's just me realizing the split between the bike segments.
But as an engineer, try to get your hands on an ebike with Pinion drive train.

Larger rotors are harder to get quiet. In particular after you had fading rotors may get out of true and then start "singing".

Btw. Blasting down the alps with 100 km/h on a road racing bike, the rider is not using the brakes at all. Way too much risk to get unbalanced. The rider would just cautiously raise head and shoulders to get down to 80. And then maybe cautiously starting to feather the brakes.

Good morning - for everyone interested in a great daily rider with electronic power support - have a look at the Specialized Turbo (S) - it's become my weapon of choice when being in Munich during the week, no more need for a car if you invest some bucks in good rainclothes (and YES, I do wear a suit during the day) plus some good bags.